from The American Heritage® Dictionary of the English Language, 4th Edition
- transitive v. To make invalid; nullify.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- v. To make invalid. Esp. applied to contract law.
from the GNU version of the Collaborative International Dictionary of English
- transitive v. To render invalid; to weaken or lessen the force of; to destroy the authority of; to render of no force or effect; to overthrow.
from The Century Dictionary and Cyclopedia
- To render invalid; destroy the strength or validity of; render of no force or effect.
- Specifically In law, to deprive of binding force or legal efficacy: as, fraud invalidates a contract.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. show to be invalid
- v. take away the legal force of or render ineffective
- v. declare invalid
- v. make invalid for use
From in- + Latin valere ("to be strong"); literally, “to make not strong”. (Wiktionary)